Up to that point, most of the research accomplished within the Research Center had a reasonably direct and obvious tie to answering problems of concern in our efforts to develop missiles
and rockets. Even the cosmic ray experiments were
largely motivated by the desire to acquire knowledge of the behavior of high performance liquid
fuel rockets; the high-altitude physics measurements more or less went along for the ride. However, there was .. no rule requiring that research
undertaken within the Research Center have any
visible relevance to Laboratory development tasks.
The wisdom of this policy was amply illustrated
by the results of a small research program undertaken in late 1957 after the Russians launched
Sputnik, the first artificial satellite, into orbit about
the earth. Two physicists, William H. Guier and
George C. Weiffenbach, used Laboratory equipment to monitor the transmissions from the satellite. They made the remarkable discovery that it
was possible to determine a quite accurate orbit for
Sputnik simply by analyzing the Doppler shift, the
frequency change imposed on the received signal by
the relative motion of the satellite and the ground
observing point. This fact was by no means obvious and it is true only because of the severe constraints imposed on the geometric path of an object
that is orbiting the earth. McClure realized that the
inverse problem-of determining an unknown location on earth by monitoring the signal for a
satellite in a previously established orbit-would be
even easier and would provide the means for at-sea
navigation of unprecedented accuracy. This led to
the Laboratory proposing the development of the
Transit navigation satellite. The concept was enthusiastically supported by the Polaris project of
the Navy as a potential solution for one of their
most difficult problems, which was how to maintain a precise knowledge of the position of a submarine at sea after weeks on station. Support was
quickly provided and the APL Space Department
was established under Kershner to carry out the
development. Thus a major Laboratory program,
which for many years accounted for approximately
one third of the Laboratory's efforts, was a direct
outgrowth of a modest research program undertaken in the Research Center without initial expectation that it might have direct developmental
significance.
It is interesting that the symbiotic relationship
between pure research and a development program
can operate in either direction. Not only did the
Transit program grow out of pure research, but it
also led directly to additional pure research by the
Laboratory in several new areas. For instance, it
turned out that to determine Transit satellite orbits
with sufficient precision required much more detailed knowledge of the gravity field of the earth
than was available from previous geodetic research.
Fortunately, the geodetic measurements made by
the Transit satellite proved to be the most useful
January-March 1980
ones made to date. We were able to produce a fine
geodetic model as early as 1964. Less obvious is the
fact that the Transit program caused us to resume
the high altitude physics measurements that had
been started under Van Allen at the end of the
War. This happened because the design of a satellite that could survive in the high altitude environment required a detailed knowledge of that environment.
There are now five Transit satellites in operation,
three of which have been working continuously for
more than twelve years and show no sign of failing. There is also widespread Navy use of Transit
on surface ships as well as on submarines and a
very substantial commercial sale of Transit equipment for ships as small as fishing boats, for ocean
drilling rigs, and for research platforms. Currently,
the number of commercial users doubles annually.
As for Navy use, perhaps I can do no better than
quote from a letter written by Chief of Naval Operations to Chief of Naval Material on June 26,
1979 stating (in part) that "It has been determined
that Omega receivers are not required on those surface ships which have had a Transit navigation
system installed. This is due to the low accuracy of
Omega as compared to that provided by Transit.
Furthermore ... the use of an electronic backup for a
system with the proven reliability of Transit cannot
be justified."
GENESIS OF THE
COLLABORATIVE BIOMEDICAL PROGRAM
Joe T. Massey
Several of the Laboratory's civil programs,
among them the collaborative biomedical program,
had their origins within the Research Center. The
biomedical program was initiated formally in the
mid-1960's, by Frank T. McClure, Robert W.
Hart, Alvin G. Schulz, and myself, who were then
members of the Research Center, and by Richard
J. Johns, Chairman of the Biomedical Engineering
Department of The Johns Hopkins University
School of Medicine. I shall briefly describe the program's genesis, summarize the first 10 years of its
life, and discuss its relationship with the Research
Center and with the Laboratory as a whole.
Following a 1965 decision to explore formally the
application of the physical sciences and technology
to the solution of medical and biological problems,
a series of seminars was held at the Laboratory
with Dr. A. E. Maumenee and the faculty of the
School of Medicine's Department of Ophthalmology to seek out problems, propose solutions, and
learn each other's specialized vocabulary. A comprehensive program resulted in which Research
Center scientists and their counterparts in the
Department of Ophthalmology identified projects
Dr. Joe T. Massey is the Director of Biomedical Engineering
Programs.
5
in a number of clinical and research areas. A collaborative grant proposal, submitted to the National Institute of Neurological Diseases and Blindness (NINDB), was funded in the spring of 1967
and was the seed from which our current collaborative program has sprung.
The ophthalmology program remains one of our
larger areas of collaboration and has turned out to
be highly productive in a number of areas. Three
examples follow.
One of the dreaded consequences of diabetes
is a complication known as diabetic retinopathy in which the eye's retina grows fragile new
blood vessels and eventually connective tissue,
leading to blindness. Working with Dr. Arnall
Patz, current chairman of the Department of
Ophthalmology, a photocoagulator that uses
an argon laser as a source was developed. The
photocoagulator seals off noninvasively
(through the cornea) the new blood vessels by
local intensive heating. Subsequent long-term
followup of patients treated in this manner by
commercial versions of the instrument indicates the efficacy of the technique, which has
become the clinical procedure of choice. The
previous alternatives were removal of the
pituitary gland or ablation of large areas of
the peripheral retina.
During the 1950's, premature infants were
commonly placed in a breathing atmosphere
containing up to 95070 oxygen. It was discovered that this led to a disease known as retrolental fibroplasia, which resulted in blindness.
Application of scientific methods of measurement using the retina of a just-born kitten as a
model resulted in the determination of safe
levels of oxygenation for the premature infant.
The ophthalmologist normally explained the
transparency of the cornea by assuming that
the fibers that comprise its structure lie in a
regular geometrical order, in spite of conflicting evidence from the electron microscope. Research Center scientists applied to the cornea a
theory used to explain the characteristics of
certain liquids. This gave the interesting result
that the apparently disorderly arrangement of
fibers as shown by the electron microscope was
consistent with corneal transparency. The experimental techniques that confirmed this theory are now used to assess corneal damage.
At about the same time, a collaborative program
in image processing was formulated that involved
Research Center scientists and faculty of the Biomedical Engineering Department, at that time a
division of the University's Department of Medicine. That program was also subsequently funded
by the National Institute of General Medical
Sciences. Here are two examples.
A device was developed that can project,
from data taken in a particular manner using a
standard X-ray instrument called a polytome,
6
an optical three-dimensional image of the region that was X-rayed.
A way was developed to process the data
from two-dimensional ultrasonic images of the
heart's left ventricle to determine how volume,
shape, and wall thickness vary during successive single beats. We hope this will provide a
noninvasive means of determining the degree
of deprivation of oxygen (or blood flow) from
hearts whose vessels are partially blocked by
atherosclerotic plaque, before damage to the
muscle has occurred.
The next major collaborative effort, in 1968, was
in the field of cardiovascular research. It was the
first effort that mainly involved people from outside the Research Center. However, the Research
Center managed and fostered the program until
1972, when I was appointed Assistant to the Director, in charge of the Biomedical Programs Office.
In May 1974, I was appointed Director of Biomedical Programs for the Laboratory. The collaborative program is now one of the Laboratory's major
nondefense activities and it involves people from
many parts of APL. Although we are now separated organizationally from the Research Center, the
Biomedical Programs personnel are largely former
Research Center people, and we continue to live in
the Research Center building.
THE RESEARCH CENTER TODAY
Robert W. Hart
The Research Center is many faceted; time does
not permit enumerating its many research projects,
let alone describing its work in any detail. My objective here is to convey a sense of the Research
Center as a whole rather than to describe its scientific activities in detail.
The central purpose of the Research Center is to
develop fundamental understanding in fields of
science that are important to the Laboratory. Accordingly, it emphasizes long range fundamental
questions rather than technological applications of
science. The Research Center represents the Laboratory's "hands-on" capability in science-and
hands-on work is at least as necessary in science as
it is in engineering, which comprises the preponderance of APL's activities.
Science is very much an art and one does not
become an artist merely by watching artists. In a
sense, the Research Center is APL's window into
science: its researchers attend scientific meetings,
present research papers, publish in the literature,
write books now and then, and bring back new science to the Laboratory. But the Center is more
than a window, it is a doorway: Research Center
people pass through it into the rest of the LaboraDr. Robert W. Hart is the Assistant Director for Exploratory
Development and Chairman, Milton S. Eisenhower Research
Center.
Johns Hopkins A PL Technical Digest